Many Christians have a tendency to make statements like “I am a sinner undeserving of forgiveness”, or “I am not worthy to serve God”. Such practices likely stem from a misconception that revering God entails debasing oneself.
While overvaluing oneself (hubris / arrogance) is problematic, it is also wrong to undervalue oneself.
Matthew 6:26 New International Version (NIV)
26 Look at the birds of the air; they do not sow or reap or store away in barns, and yet your heavenly Father feeds them. Are you not much more valuable than they?
Furthermore, saying that someone is deserving (or undeserving) of something, means that they should (or should not) be given that thing. So it is technically a contradiction to on one hand claim that a Christian does not deserve forgiveness, yet on the other hand claim that God forgives that Christian anyway. Because:
[quote] if somebody/something deserves something, it is right that they should have it, because of the way they have behaved or because of what they are [/quote]
( https://www.oxfordlearnersdictionaries.com/definition/english/deserve?q=deserve )
If you searched the entire bible, you would find nothing saying that Christians do not deserve forgiveness. Actually, you would find the exact opposite:
Matthew 10:5-42 New International Version (NIV)
5 These twelve Jesus sent out with the following instructions: “Do not go among the Gentiles or enter any town of the Samaritans. 6 Go rather to the lost sheep of Israel. 7 As you go, proclaim this message: ‘The kingdom of heaven has come near.’ 8 Heal the sick, raise the dead, cleanse those who have leprosy,[a] drive out demons. Freely you have received; freely give.
9 “Do not get any gold or silver or copper to take with you in your belts— 10 no bag for the journey or extra shirt or sandals or a staff, for the worker is worth his keep. 11 Whatever town or village you enter, search there for some worthy person and stay at their house until you leave. 12 As you enter the home, give it your greeting. 13 If the home is deserving, let your peace rest on it; if it is not, let your peace return to you. 14 If anyone will not welcome you or listen to your words, leave that home or town and shake the dust off your feet. 15 Truly I tell you, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town.
32 “Whoever acknowledges me before others, I will also acknowledge before my Father in heaven. 33 But whoever disowns me before others, I will disown before my Father in heaven.
37 “Anyone who loves their father or mother more than me is not worthy of me; anyone who loves their son or daughter more than me is not worthy of me. 38 Whoever does not take up their cross and follow me is not worthy of me. 39 Whoever finds their life will lose it, and whoever loses their life for my sake will find it.
40 “Anyone who welcomes you welcomes me, and anyone who welcomes me welcomes the one who sent me. 41 Whoever welcomes a prophet as a prophet will receive a prophet’s reward, and whoever welcomes a righteous person as a righteous person will receive a righteous person’s reward. 42 And if anyone gives even a cup of cold water to one of these little ones who is my disciple, truly I tell you, that person will certainly not lose their reward.”
( https://www.biblegateway.com/passage/?search=mat+10%3A5-42&version=CEB;NIV;NET;NRSV;YLT )
In short: Jesus sends his twelve disciples to “the lost sheep of Israel” (v5), searching for worthy Christians. He even gives explicit criteria (v37) that would identify unworthy ones who are to be condemned (v15).
You may also hear misguided preachers speaking of God’s justice and mercy as though they were opposites, e.g. “God’s justice demands that the sinner be condemned, but Gods mercy demands that the sinner be forgiven”. Sounds cool, but is actually unbiblical. When a sinner confesses his sin (i.e. repents), God will forgive not only out of mercy, but also because it is the just / righteous thing to do.
1 John 1:9 New International Version (NIV)
9 If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.
( https://www.biblegateway.com/passage/?search=1+john+1%3A9&version=CEB;NIV;NET;NRSV;YLT )
Christianity is flooded with such misconceptions on key philosophical ideas, because most Christians are unaware of the sea of lies they are swimming in. They carelessly drink the kool-aid perpetuated by popular preachers who attract swathes of followers by their elaborate displays of piety.
1 The quality of being religious or reverent.
‘acts of piety and charity’
1.1 [count noun] A belief which is accepted with unthinking conventional reverence.
‘the accepted pieties of our time’
Instead of asking the far more difficult question of “is this true”, Christians usually resort to the inadequate test of “does this sound pious”, which is why they end up learning false ideas produced by preachers engaging in what I’d call “theological one-upmanship”.
Truth says: “forgive if the sinner is repentant.”
But piety tries to do one better, and instead says: “forgive regardless of the sinner’s remorse”.
Truth says: “God forgives some but not others, because some actually deserve forgiveness, while others don’t.”
False piety says: “God is super awesome, while in comparison humans are all unworthy junk and hence deserve hell …”
Finally, here’s an easy way to identify much of the pious gibberish you may witness on your Christian journey:
If it comprises a short, catchy phrase / sentence, sounds kinda impressive, but somehow the biblical authors were apparently too stupid to simply express it that way in the bible, then it’s probably some bullsh*t that at best oversimplifies what the bible is trying to say, and at worst is saying something completely false.